C. Deerenberg: Parental energy and fitness costs in birds. 1996 T. de Boer: Sleep regulation in the Djungarian hamster. The effects of temperature, photoperiod and daily torpor. 1997 P.M. Meerlo: Behavioural and chronobiological consequences of social stress in rats. 1997 K.C. de Kogel: Long-term effects of brood size on offspring. An experimental study in the Zebrafinch. 1999 A.M. Strijkstra: Periodic euthermy during hibernation in the European ground squirrel: causes and consequences. 1999 P.E. Boon: Daylength and growth: Behaviour, energy balance and protein synthesis. 1999 M.J.H. Kas: Sleep and circadian timekeeping in Octodon degus. 2000 I.R. Pen: Sex allocation in a life history context. (cum laude) 2001 R.A. Hut: Natural entrainment of circadian systems. A study in the diurnal ground squirrel Spermophilus citellus. 2001 K. Jansen: Circadian rhythms in pacemaker and behavior. (a study in the Common vole, Microtus arvalis) 2001 M. Oklejewicz: The rate of living in tau mutant Syrian hamsters. Studies on the impact of a circadian allele on temporal organisation. 2002 B.I. Tieleman: Avian adaptation along an aridity gradient. Physiology, behavior, and life history. (cum laude) 2003 C. Carere: Personality as an epigenetic suite of traits. A study on a passerine bird. 2003 B. Riedstra: Development and social nature of feather pecking. 2003 B.A.M. Biemans: A time to remember. Consequences of ageing on the circadian memory modulation in rodents. 2004 C.M. Eising: Mother knows best? Costs and benefits of differential hormone allocation in birds. 2004 W. Müller: Maternal phenotypic engineering. Adaptation and constraint in prenatal maternal effects. 2004 N.B. Baron von Engelhardt: Proximate control in avian sex allocation - a study in zebra finches. 2005 M. Rüger: Lighting up the human clock: Effects of bright light on physiological and psychological states in humans. 2005 K. Spoelstra: Dawn and Dusk. Behavioural and molecular complexity in circadian entrainment. 2005 S. Engel: Racing the wind. Water economy and energy expenditure in avian endurance flight. 2006 P.D. Dijkstra: Know thine enemy. Intrasexual selection and sympatric speciation in a Lake Victoria cichlid fish. 2006 P. Korsten: Avian sex allocation and ornamental coloration. A study on blue tits. 2007 C. Schmidt-Wellenburg: Costs of migration. Short- and long-term consequences of avian endurance flight. 2007 L.M. Vaanholt: The rate of living in mice. Impacts of activity and temperature on energy metabolism and longevity. 2007 A. Zavada: Defining and determining the properties of the human sleep homeostat. 2007 D. van der Veen: Neural substrate and the timing